perthite
|per-thite|
🇺🇸
/ˈpɜrθaɪt/
🇬🇧
/ˈpɜːθaɪt/
exsolved alkali-feldspar intergrowth
Etymology
'perthite' originates from English, specifically formed from the place name 'Perth' plus the mineral-forming suffix '-ite', indicating a mineral or rock associated with that locality.
'perthite' was coined in modern English by combining the locality name 'Perth' with the suffix '-ite' (common in mineral names) and came to denote the specific feldspar intergrowth observed in specimens from that or similar localities.
Initially used as a locality-based mineral name ('a mineral/texture associated with Perth'), it evolved into a technical petrological term meaning 'an exsolution intergrowth of albite in K-feldspar.'
Meanings by Part of Speech
Noun 1
a texture or intergrowth in alkali feldspar in which distinct lamellae or layers of a sodium-rich feldspar (albite) occur within a potassium-rich feldspar (orthoclase or microcline) as a result of exsolution.
Thin sections of the rock show clear perthite lamellae under the microscope.
Synonyms
Last updated: 2025/11/13 09:12